Survey on the Policy Evolution of China s Marine Carbon Sink and Carbon Trading Market

Climate change is currently the biggest environmental challenge facing sustainable development in human society,and it is an inherent requirement for achieving sustainable development by actively addressing climate change.Under the increasingly strict constraints of climate governance,developed countries such as the United States,European Union countries,and Japan have responded and actively formulated low-carbon development goals and policy measures that are in line with their national conditions.These policies mainly involve various fields such as low-carbon technology,energy conservation and emission reduction,and circular development,with clear policy guidance.In this paper,the evolution of policies on marine carbon sink and carbon trading in China is summarized,providing support for better understanding the background of formulating relevant international and domestic policies.

Biocontrol of Rhizoctonia solani Kühn Using Fermentative Solution of Streptomyces corchorusii Strain NF0919

A strain of Streptomyces corchorusii （NY0919） antagonistic to Rhizoctonia solani Ktthn was isolated, which produced alkyl glycoside with high antifungal activity. To investigate the antifungal activity of Streptomyces corchorusii strain NF0919, the treatments amended with the non-sterilized supernatant resulted in the highest growth inhibition rate of about 100% at a concentration of 20%. The antifungal compound, which inhibited the growth of Rhizoctonia solani Kuhn, was extracted by EtOAC and purified by silica gel, Sephadex LH-20 column, and HPLC, where an active fraction was confirmed by LC-MS and NMR techniques. These results suggested that NF0919 had a high potential in the biocontrol of Rhizoctonia solani Kuhn, which was mainly due to surface active agent APG.

磷钨酸促进的酰肼与查尔酮缩合反应的研究

本文以杂多酸–磷钨酸为催化剂,对酰肼与查尔酮的缩合反应进行了研究。经过一系列反应条件的筛选,确立了最佳反应条件,并对底物的普适性进行了考察,得到了一系列高产率的酰腙类目标产物,最高产率达到99%。本反应操作简单,条件温和,为查尔酮酰腙合成提供了一种新的方法。

Comparison of Soil Nutritional Status between Different Muscat Hamburg Vineyards in Coastal Areas of Tianjin

To study the effects of different soil conditions on winter nutrient storage of Muscat Hamburg branches,this study compared the soil texture,bulk density,total salt content and soil K,Ca,Na,Mg and total Fe contents of Muscat Hamburg vineyards in Ninghe District and Hangu District,Binhai New Area of Tianjin and analyzed the soluble sugar and soluble protein contents in one-year-old vine branches. The results showed that the soil p H was lower,and the soil K,Ca and total salt( 0. 445%) contents were higher in the vineyard of Ninghe District than those in the vineyard of Hangu District. There were no significant differences in the soil Mg,Fe and Na contents between the vineyards in the two regions. The soil of the vineyard in Ninghe District is medium loam,and that in Hangu District is heavy loam. In short,all the soil indicators of the vineyard in Ninghe District were better than those in Hangu District except the indicator of soil salt content. The soluble sugar and soluble protein contents of one-year-old vine branches differed significantly between the two regions.

Force-Triggered Guest Release from Mechanophore Incorporated Rotaxanes

We have developed a rotaxane-based mechanophore system that is capable of breaking a mechanical bond and releasing small molecules via force-triggered rotaxane disassembly.In this design,a cyclobutane mechanophore was fused to the ring component of a rotaxane,constructed through a template-mediated synthesis in high yields.Upon opening the ring component,the rotaxane disassembled to release the axle molecule.We successfully demonstrated and quantified the force-triggered release of the axlemolecule in both solution and solid-state samples.

Sedimentary environment and major controlling factors of organic matter-rich shale from the Wufeng-Longmaxi formation in eastern Sichuan Basin,China

The major controlling factors of organic matter and its enrichment model of the black shale from the Wufeng-Longmaxi Formation were explored by investigating the vertical variation characteristics,as well as major element and trace element abundances in the Wuxi Bailu section.The results show that the sedimentary tectonic setting of the Wufeng-Longmaxi Formation in the north-east margin of the upper Yangtze platform is located on the active continental margin,which is a passive continental margin and continental island arc.The parent rock in the source area is mainly felsic volcanic rocks mixed with small amounts of sedimentary recycling materials.Due to increased plate activity and a drop in sea levels,terrigenous pyroclastic input increased.The palaeoclimate was semi-humid,and a robust dysoxic-reduction environment and a high level of palaeoproductivity,causing the formation of the organic-rich shale in the Wufeng Formation.At the base of the Longmaxi Formation,the sedimentary water body was affected by global transgression,showing a strong anoxic-reductive environment,and the paleoclimate was a warm and humid condition.The palaeoproductivity level was high,resulting in the formation of organic shale.Due to the sea level drop at the top of the Longmaxi Formation,the sedimentary water was in an oxic-reduced environment,but the input of terrigenous pyroclastic matter increased.Because the paleoclimate was warm and humid and the palaeoproductivity level was high,organic-rich shale was formed.The findings demonstrate that terrigenous clastic input circumstances,palaeoproductivity conditions,and paleo-redox conditions had the greatest influence on the enrichment of organic matter in the Wufeng-Longmaxi Formation.Thus,organic matter enrichment was controlled by multiple paleoenvironmental factors.

Increasing prevalence of antibiotic resistance genes in manured agricultural soils in northern China

Land application of manure tends to result in the dissemination of antibiotic resistance in the environment.In this study,the influence of long-term manure application on the enrichment of antibiotic resistance genes(ARGs)and mobile genetic elements(MGEs)in agricultural soils was investigated.All the analyzed eight ARGs(tetA,tetW,tetX,sull,sulll,ermF,aac(6')-Ib-cr and blaTEM)and two MGEs(intJJ and Tn916/1545)were detected in both the manured and control soils,with relative abundances ranging from 10^-6 to 10^-2 Compared with the control soil,the relative abundances of ARGs and MGEs in manured soils were enriched 1.0-18.1 fold and 0.6-69.1 fold,respectively.High-throughput sequencing analysis suggested that at the phylum level,the bacteria carrying intll and ermF might be mainly affiliated with Proteobacteria and Bacteroides,respectively.The dominant genera carrying intll and ermF cow\d be Pseudomonas and Bacteroides,independent of manure application.Correlation analysis revealed that ARGs had strong links with soil physicochemical properties(TC,TN,and OM),heavy metals(Cu,Zn and Pb)and MGEs,indicating that the profile and spread of ARGs might be driven by the combined impacts of multiple factors.In contrast,soil pH and C/N exhibited no significant relationships with ARGs.Our findings provide evidence that long-term manure application could enhance the prevalence and stimulate the propagation of antibiotic resistance in agricultural soils.

Real-time transition dynamics and stability of chipscale dispersion-managed frequency microcombs

Femtosecond mode-locked laser frequency combs have served as the cornerstone in precision spectroscopy,alloptical atomic clocks,and measurements of ultrafast dynamics.Recently frequency microcombs based on nonlinear microresonators have been examined,exhibiting remarkable precision approaching that of laser frequency combs,on a solid-state chip-scale platform and from a fundamentally different physical origin.Despite recent successes,to date,the real-time dynamical origins and high-power stabilities of such frequency microcombs have not been fully addressed.Here,we unravel the transitional dynamics of frequency microcombs from chaotic background routes to femtosecond mode-locking in real time,enabled by our ultrafast temporal magnifier metrology and improved stability of dispersion-managed dissipative solitons.Through our dispersion-managed oscillator,we further report a stability zone that is more than an order-of-magnitude larger than its prior static homogeneous counterparts,providing a novel platform for understanding ultrafast dissipative dynamics and offering a new path towards high-power frequency microcombs.

Stimulated generation of deterministic platicon frequency microcombs

Dissipative Kerr soliton generation in chip-scale nonlinear resonators has recently observed remarkable advances,spanning from massively parallel communications, to self-referenced oscillators, and to dual-comb spectroscopy.Often working in the anomalous dispersion regime, unique driving protocols and dispersion in these nonlinear resonators have been examined to achieve the soliton and soliton-like temporal pulse shapes and coherent frequency comb generation. The normal dispersion regime provides a complementary approach to bridge the nonlinear dynamical studies, including the possibility of square pulse formation with flattop plateaus, or platicons.Here we report observations of square pulse formation in chip-scale frequency combs through stimulated pumping at one free spectral range and in silicon nitride rings with +55 fs~2∕mm normal group velocity dispersion.Tuning of the platicon frequency comb via a varied sideband modulation frequency is examined in both spectral and temporal measurements. Determined by second-harmonic autocorrelation and cross correlation, we observe bright square platicon pulse of 17 ps pulse width on a 19 GHz flat frequency comb. With auxiliary-laser-assisted thermal stabilization, we surpass the thermal bistable dragging and extend the mode-locking access to narrower 2 ps platicon pulse states, supported by nonlinear dynamical modeling and boundary limit discussions.

Multitarget tracking control algorithm under local information selection interaction mechanism

This study focuses on the problem of multitarget tracking.To address the existing problems of current tracking algorithms,as manifested by the time consumption of subgroup separation and the uneven group size of unmanned aerial vehicles(UAVs)for target tracking,a multitarget tracking control algorithm under local information selection interaction is proposed.First,on the basis of location,number,and perceived target information of neighboring UAVs,a temporary leader selection strategy is designed to realize the local follow-up movement of UAVs when the UAVs cannot fully perceive the target.Second,in combination with the basic rules of cluster movement and target information perception factors,distributed control equations are designed to achieve a rapid gathering of UAVs and consistent tracking of multiple targets.Lastly,the simulation experiments are conducted in two-and three-dimensional spaces.Under a certain number of UAVs,clustering speed of the proposed algorithm is less than 3 s,and the equal probability of the UAV subgroup size after group separation is over 78%.